From best-selling authors, psychologists, and leaders who understand what it takes to develop resilience.

We tend to think confidence is an innate personality trait that you have or you don't. We make the mistake of assuming we have to feel confident before taking action, so we put off launching a business or pursuing big goals. But the truth is, confidence is cultivated. It's a skill that's reinforced with the right daily habits.

Action, actually, is the key to developing self-confidence. It's one thing to learn to think positive, but when you start acting on it, you change yourself, one action at a time. You are what you do, and so if you change what you do, you change what you are.

Making mistakes and recovering from them actually helps you feel better about yourself, proving grit is built, not inborn.

Best-selling author and entrepreneur, Denise Duffield-Thomas, knows a thing or two about developing resilience. Today she runs a million-dollar business while also being a mom of two.

So what small steps can you take to grow your confidence? Here's some hard-earned wisdom, gleaned from Duffield-Thomas and other self-made millionaires along with practices backed up by science:

1. Mind your mindset.

Your beliefs about what you're capable of can make or break your success. "It's not lack of ambition or intelligence that holds most people back", says Duffield-Thomas, "You can fake it 'til you make it, but that won't change how you feel on the inside."

2. If you doubt yourself, you're doing it right.

Over 70% of people struggle with Imposter Syndrome, including many of the world's most successful people. In fact, it's felt more acutely by intelligent, highly accomplished individuals, according to Imposter Syndrome researchers Dr. Pauline Clance and Suzanne Imes.

Fear of failure and the unknown is natural, especially when you're a high-achiever who is constantly pushing yourself. Counterintuitively, experiencing doubt is a sign of progress -- an inevitable right of passage in entrepreneurship -- says Duffield-Thomas, "Worrying that people think you're a fraud isn't a sign that you're not meant to be successful. It's just an inevitable signpost along the way of success".

3. Pick one micro-goal to overcome procrastination.

If you try to do too much, you'll end up distracted, overwhelmed, and discouraged, which is not a recipe for high self-esteem.

Research from Stanford behavioral psychologist BJ Fogg shows that creating small, micro-goals is the best way to build positive momentum.

4. Accentuate the positive.

We've already established that your beliefs can influence your confidence, but Duffield-Thomas argues you shape your success through the use of simple phrases, what she calls money affirmations. Her favorite? "'I serve, I deserve.' It instantly reminds you that when you do good in the world, good is sure to come back to you."

Before you go dismissing this as too woo-woo, there's ample evidence that making a conscious effort to focus on the positive helps overcome our natural negativity bias. By doing so, you gradually train your brain to become more resilient.

One writer -- and self-proclaimed "negative Nancy" -- said reciting money affirmations for week brought her an immense sense of peace, control, and new streams of income. It's okay if you're skeptical. Try it and see if it works for you.

5. Be grateful.

Many of the world's most successful people swear by a daily gratitude practice:

Oprah says she kept a gratitude journal for ten years without fail during her ascent to stardom.

Entrepreneur Tim Ferriss, who has spent his career studying the habits of top-performers, journals about what he's grateful for as part of his morning routine.

Even Sir Richard Branson credits an attitude of gratitude for helping him maintain his sense of optimism.

"We overlook things each day like freedom, fresh air to breath, and food to drink," says Duffield-Thomas, "but also so many opportunities, and forms of support we have around us that build a foundation of confidence and encourage us to believe in ourselves."